Lpc2000

One problem, in order to do what you want you will need an external 
null modem cable, or use a 2nd UART.

The most commonly used xtal frequencies are 11.0592 and 14.5796, 
both of these allow the full range of baud rates.  The choice of 
which one to use will depend on what speed you want to run the chip 
at.  If you check in the user's guide for the LPC2214 you should 
find the information for both processor speed and baud rate 
generation formulai.

GIYF - google is your friend :)  You can find everything you are 
looking for there in regards to how to interface a modem to a micro.

-- Sean

--- In lpc2000@yahoogroups.com, "bhimanipankaj" <bhimanipankaj@y...> 
wrote:
>
> Dear ARMiesssss.........
> 
> I am very new to ARM world ,I am interfacing serial port with 
lpc2214
> that is db9 connector and want to programme my lpc2214 with the 
same
> as well as I want to interface an external modem so can I use same
> serial port for both the purpose??
> 
> What should be the ideal crystal frequency which could be best for 
my
> case.
> 
> for serial communication I read UART part from the manual and GPIO
> part what else I need to study for that? GUIDE ME PLEASE